1. Field of the Invention
The present invention is directed to an x-ray examination apparatus, and in particular to such an apparatus having an x-ray image intensifier and an x-ray film changer, with the film changer being mounted so as to be optionally moveable into an exposure position in front of the x-ray image intensifier.
2. Description of the Prior Art
An x-ray examination apparatus having an x-ray image intensifier, with an x-ray film changer mounted so as to be optionally introducible into the beam path in front of the x-ray image intensifier for producing x-ray pictures is commercially available from BC Medical Manufacturing Company Limited, and is described in a brochure from that company. In this commercially available apparatus, the x-ray image intensifier has a holder attached thereto, on which the x-ray film changer is mounted so as to be moveable, with the x-ray film changer in the exposure having the same image access as that of the image intensifier. The film changer can be pivoted out of the exposure position by approximately 90.degree. to a standby position.
The above commercially available installation is suitable, for example, for conducting angiography examinations. In such an examination, the introduction of a catheter into the patient is tracked using the x-ray image intensifier. When a contrast agent is then injected into the patient via the catheter, x-ray exposures are frequently made, for which purpose the x-ray film changer is brought into the exposure position. After the x-ray exposures have been made, the x-ray film changer is again pivoted back to the standby position. In this known x-ray examination apparatus, the holder for the x-ray film changer is rigidly attached to the image intensifier, so that the film changer has only a single standby position. The brochure of BC Medical Manufacturing Company Limited for this apparatus shows one standby position, at which the x-ray film changer lies at the head side, and behind the image intensifier, as seen by a patient lying on an examination table. This standby position of the x-ray film changer is particularly cumbersome for an anesthesiologist because the patient is difficult to reach proceeding from the head side. A further disadvantage of the standby position of the x-ray film changer is that, given a cranial angling of the x-ray image intensifier, the film changer will press against the stomach or chest of the patient, thereby limiting the available angular displacement.